diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/pm/priv.h b/drivers/gpu/drm/nouveau/nvkm/engine/pm/priv.h
index 6ae25d3e7f45..c011227f7052 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/pm/priv.h
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/pm/priv.h
@@ -82,7 +82,7 @@ struct nvkm_perfdom {
 	u8  mode;
 	u32 clk;
 	u16 signal_nr;
-	struct nvkm_perfsig signal[];
+	struct nvkm_perfsig signal[] __counted_by(signal_nr);
 };
 
 struct nvkm_funcdom {